[Bruce Lancaster]

We need to fire up some old-timers for those procedures! There were several schools of thought, welding on a lump of stock atop lifter, brazing on a piece of steel, etc., then grinding to fit in the old B&D.
I've always used Johnsons, but I recently lost my last spare jar of those and I'm down to a single used set, needing a bit of base grinding of course. Used ones now are drawing gold prices. Time to learn more of the old ways!
I still remember the day the Johnsons died, a long time ago now.
The Johnsons I planned to use had grown a light coat of rest in the basement, and since lifters were like $20 a set I just ordered another set. The box when it arrived was disturbingly heavy...those solid ones with fake Johnson windows cast in the sides had replaced Johnsons, and that was that! I carefully cleaned up the rusty Johnsons and buried the heavies deeeeep in the basement.
The extra weight of the actual Johnsons was pretty trivial. The extra weight of the solids is quite a lot...in a street engine I suspect it does nothing noticeable, as streetable flatheads don't even need much spring, but the things are very unappealing. All that extra weight is bad even if it doesn't affect anything.

Anyway...for you...first check out dimensions with stock lifters and your cam. If they are too short, it's hard to grind on extra length...