Gearbox oil seal replacement

Greetings fellow TFers I've not been on much recently as I've been busy welding a MGB GT, and the TF has been running fine despite being thrashed weekly back and forth between Bath and Plymouth.

However at the last MOT I noticed the beginnings of an oil leak from the offside gearbox seal ( my MOT tester is old school and is happy for me to wander around under the car whilst it is on the hoist). I put the car up on ramps yesterday and it has got worse - I had to add 800ml of oil to the gearbox. So time to replace the seal.

I've checked and being a PG-1 box the seals are available from various suppliers, including mgmania, however I notice one of the Lotus Elise suppliers supply an 'Enhanced ' seal - is there any issue with standard seals supplied by reputable suppliers?

Otherwise looks fairly straightforward- anyone who has done this have any watchits I should be aware of? I note there used to be a special tool TRV100060 specified - was this to protect the lip seal when inserting the drive shaft? What was this tool made of as unless it was flexible I can't see how you would remove it after fitting the drive shaft? I might wrap a piece of thin plastic around the shaft end if necessary when inserting.

I can't help you with the Lotus Elise seal.

When I replaced my seals recently I used a length of 4x4 timber to knock the seal in square.

14. Fit seal protector, tool 18G 1269A to input
shaft, or apply masking tape to splines to
protect oil seal.
15. Place input and output shafts together and fit
assembly in differential housing.

This is from the RAVE manual (available on here) and has a completely uninformative picture with it, so masking tape it is!