What light weight lifters are you talking about?? Is it the lightweight lifters AC.net sold a good 6+ yrs ago with the real small lifter body??? are you talking about schubeks?
A handy dandy machinist can probably ream out the silicon bronze sleeves you already have. Give them a sample lifter so they can match the bores with the OD of the lifter body.
My only concern is that the machine shop didn't index the lifterbores with the existing bores. Alot of reputable vw machine shops have a jig to perfetly align the bores. Ask if Rimco has a jig?

? HMMM?

Indexing a lifter bore sleeve with "old one" isn't good!!
A friend of mine used the heavy duty aluminum pushrods with 7mm stemmed valves, schubeks, stiff VW OD dual valve springs and he now owns 45 degree angled pushrods

Low revving street cars can benefit from aluminum pushrods but I'd use a heavier taper pushrod for rigidity for a high revver. The smith brothers/jaycee/GB 160,000 psi pushrods work extremely well but a marginal amount of potential for some flex because they are straight.
louis, if your willing to go with a CB aluminum case that would give you everything you want straigtht out of the box. 1 way shipping to your door. If and when the aluminum lifterbores go oval you can get it sleeved with silicon bronze.
OR
Take the time and do not waste a new "butchered" AS41 case. Get it fixed and abuse it to your hearts content
