Series 3 Rear Engine Bearing

Rebuilding my 3brg Engine, time to tackle the Infamous rear main Bearing seal.
so i have the seals & T Pieces,
made the mistake possibly of having already fitted Crank & Pistons before doing this last bearing...

any Top Tips... youTube is full of videos showing tow Matel plates used to Guide the T Pisces into the Housing... How / Where do I find these????

https://www.hnjengineering.co.uk/pages/products/hnj270304/hnj270304.html

or you could make a couple hard plastic out hardwood if not metal

expensive , when I did mine I tried lightly clamping either side and also pushing each side in with screwdriver while tapping housing down , might also help,a bit having housing in freeezer In bag for a couple of hours,

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