Yea, it is a good question and no I didn't shoot the rifle for group before it got sent off to have the scope installed, so I am just gonna have to accept that the cost of the bedding was worthwhile, without actually knowing if that is true.
I got a reproduction No4(T) cheekpiece. If that worked for the WWII snipers then I'm sure I can make it work.
That repro cheek piece will work just fine and it's not going to devalue anything now. Just make sure you fit it properly, so it isn't to close to the wrist. Likely it will need to have some wood removed on the bottom to fit snugly and it may require some to be removed from the top, to get your eye in line with the center of the scope, which has parallax up the hoop and if you don't keep your eye centered, groups will not be good.
I've never had a No4 MKII, other than a few that were bubbaed that shot poorly.
The No4 MKII are likely the cream of the last of the Lee Enfield models made for military purposes.
The Australian AIA versions all shot very well but of course, they were built for the civilian markets and they had some definite changes that were quite good.
Many of us have built something that we just had to have and damn the cost.
At least you didn't start out with a clunker and try to turn a sow's ear into a silk purse.
If you wait long enough and have an itch to sell it, you will very likely recoup your overall costs.
I saw a couple of No4 MKI ''faux" snipers, that looked very good on the outside.
I didn't bother to handle them, they were priced over $3000 and my interest waned instantly at that price.
Whatever, shoot it, because that's what you built it for and have fun.