My new method to install triple-seals on 348

I posted this earlier this year in the Mondial section, but I think it may garner more interest in the 348 section. Here is the earlier post (with some additional information added):

Following two driving seasons on the road after having acquired my Mondial t, a slow leak of brake fluid started to appear last November under the clutch pumpkin. So I decided to do a full clutch service over the winter, besides I do not have any service history or records so I was also starting to worry about how worn out the clutch plate may be. As part of the clutch service, I decided to replace the triple seals thinking this must be an easy thing to do. I studied the excellent videos and write-ups about this on youtube and fchat. I then followed the method where you first boil the seals in water and then place them on the shaft. I tried this but then ran into the problem that others seem to have encountered where the seals end up larger in diameter since they are stretched when they are moved along the splined drive shaft to their respective final positions. I came to realize that triple-seal replacement is non-trivial.

I then came up with the theory that they end up stretched since they are warm when put on but then cool off quickly as they are moved down the shaft. I reasoned that as a seal cools off, the seal's inner diameter becomes equal to the outer diameter of the shaft. As a result the seal's diameter becomes larger and it is then difficult to get them into the outer drive shaft.

To try to solve this problem, I reasoned that the trick may be to somehow keep the seals and the shafts all warm until they are each in their required resting places and pushed back into the outer shaft. To do this, I built the contraption shown below using 3 heat guns from Harbor Freight, metal ducting/sheathing, and a piece of plywood. The plywood is fixed to the studs on the clutch housing. The heat guns have low and high positions so the temperature can be regulated quite easily as needed. To push the seals along the shaft, I used a standard 1 inch chrome plated drain pipe (used typically under sinks in America), as shown below, that happens to fit perfectly. The technique worked surprisingly well. After one practice seal installation to establish the routine, I did the three in a matter of minutes with no complications. Since the installation in March, I have driven about 600 miles this season and there is no leaking.

Here is a summary of the steps I followed: (1) remove the “4th seal” (this black rubber o-ring can be put on later), (2) heat up the shafts and keep the heat on until the very end (may need to regulate heat so as not to become over heated), (3) place seal at end of shaft to warm it up for about a minute, (4) when seal feels softer, nudge warmed seal (by hand) onto shaft end, (5) push seal along the shaft with 1 inch drain pipe, (6) nudge seal (by hand) into final position, (7) repeat for all three seals, (8) push shaft in while nudging warm seals into outer shaft (by hand and using a blunt tool), keeping temperature up all during this time, (9) let everything cool off completely, (10) install round metal clip on splined shaft, (11) install "4th seal."

The difficult part is to try to complete this without burning your hands, a glove on one hand did help. I hope this contribution may be useful. I guess the method may also be applicable to 355 and others that may also have triple-seals.
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Yes, I certainly agree that it is complex, I was even laughing at myself once I had it all set up! However, I was not entirely convinced myself by the boiling method and I did not want to possibly waste further seals (I only had 5 left) since they are relatively expensive. So I felt more confident with going ahead with my contraption that seemed to me to offer a guaranteed solution. Besides, I only had to buy 2 extra heat guns (at $14.99 each) and the other materials I had lying around. It was also winter, see photo, with not much else to do with a Ferrari at the time!
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