Tinker you are on good side of 65, & still swinging strong. I'm a little jealous, but I do feel blessed to still be able to get out and walk the course on occasion.
My approach this time is moderate one so I only built club to 45.0", not way shorter as Wishon suggests. Too soon to say how that length with this shaft is going to do for me. First 9 holes Played since the build had 7 driver shots plus a mulligan which I didn't play. No fades although I tried. All went straight where I aimed. So my attempts at a cut went left. I'm used to a softer shaft, my shots aimed left were not curving either, just straight. No one has reported any experience with this Mitsubishi Bassara shaft so I'm discovering about it on my own. Hoping it does as well as it seems capable of, having almost reached 230 yd green from our senior tee box, no roll out. If I ca be half way consistent and carriy it 200, with my sub 90 mph swing, I'll be very satisfied. I'm hitting way low trajectories and need to increase my angle of attack with a swing adjustment , so pretty hopeful there's some more yds in the kitty.
Playing with swing wt another possibility for optimization I might try. It calculated on an estimate as D3, like my previous shaft, but it feels less than that now. If it works as is, I'll just call it wheel barrow and roll on.