I’m one of those that likes to tinker with shafts. My solution is Club Conex connectors (Fuse-Fit) to be specific. These allow you to swap shafts between various heads (within reason). I purchased a bunch of these from Golfworks when they handled them, you need to buy them from Club Conex now. If I recall correctly I installed them on three STW driver heads (9.5/10.5/12) and three 6 irons (adjusted lies standard +2 and -2). In addition with the shafts I set up three shafts each with L, A, R, S flex with different lengths. I use these for fitting right handers. (For left handers I have 3 6 irons and use the same shafts- for driver fitting I have a bio-cell and a hand full of shafts with cobra adapters on them).
I have a few connectors left over that I can change out when I want to test a new shaft I’ve acquired and move the connectors around to various other shafts when the need arises.
With the Fuse-Fit connectors you still use the OEM tip trim instructions, but you must strip back the paint to two inches I believe. If I do decide to use the shaft permanently, I remove the connector, slip a small piece of heat shrink (1/2″ or so) assemble as I normally do, and hit the heat shrink with my heat gun. Gives a more finished look.
Club Conex used to make a connector that you could adjust face angle with (+/- 1 degree), but they’re no longer available.
Also, the Club Conex connectors are legal for USGA play, so you can leave them in place if you so desire. They add about 9-10 grams of weight to the head.