valve stem height - need some help

I bought a set of SpeedMaster BB heads, the fully assembled, non-cnc, hydraulic flat tappet version. I'm waiting another day or two till my valve spring tool gets here to disassemble them for a check, but so far they look good with one exception - all the exhaust valve stems are a fair bit shorter than the intakes. The intakes are all the same height but of the 8 exhausts, 6 are .039 short, one is .033 short, and the last one is .048 short.

I got some good advice on using adjustable pushrods or rockers to fix the mismatch (thanks @PRH), but either of those is a several hundred dollar fix and I'm trying not to bleed cash on this project. I intended to re-use the stock pushrods, and rockers. This is not going to be a beast of an engine, just a nicely spunky and fun street car so a hydraulic cam is fine with me.

Then while snooping around for adjustable arms or rockers and getting sticker shock, I saw some very old posts from @pishta on moparchat, suggesting the use of valve stem lash caps to solve a similar situation (pishta, feel free to weigh in on this!).

If I can find the right size caps that are .040 thick to add to the exhaust valves, would that solve the problem? That would put the six stems right on, one would be .007 short and one would be .008 long. I'm assuming with hydraulic lifters, being within .007-.008 is plenty close.

Has anyone tried this and if so, how did it work? It looks like it would turn out good on paper, but getting an informed opinion is better than guessing.