Yeah, I'd say that fitting the ancillaries is the hardest part of the entire conversion!
The stupid Mopar/Motorcraft/SVT/SVO/Chip Foose-wannabe crowd have it quite good; all of that stuff is available to them over-night (and even over-the-counter at Schuck's etc.)! They come in beautifully-sorted, billet aluminium, laser-inscribed parts - ready to fit most any auxiliary component, with most any engine/gearbox/chassis combination! It's an insult to call it "custom" anymore...
In the world of
custom-custom (for the guy putting a blown GM 3.8 in a 60s Volvo wagon or something),
we - with our 24v conversions - actually have it quite good! Our starters are a direct bolt-on, as is the tail-housing and the motors sit right on the stock engine-mounts -
all of that sorted! I have the program down on the intake plenum and valve cover-conversions and brake-booster/pedal-box/brake-master/clutch-master options now, so what's left is the alternator bracket (and the P/S pump bracket for street cars and the A/C bracket - for the pansies in the sunbelt...)
It's the placement of the ancillaries that is a problem, since the transaxle chassis does a pretty severe slope - inward at the bottom - upfront! Tight in there. None of the old 164 components with 164 brackets work. None of the old Milano components and brackets work either! I have seen a picture of one conversion that appeared to use the 164 P/S bracket with the Milano P/S pump in the same location as the 164, but now the hoses change! The Milano alternator seems to fit with the Milano alternator bracket - down-left, but it fails (as we have learned) and I know from the past that it makes placement of the P/S pump a tight fit on that side!
Invariably, the hydraulics are another issue to contend with. Even that isn't standard; the Verdes have a P/S pump cooler (and only SOME of them do - at that)!

The wiring just takes time, but it is straight forward for your average "electrical-guy" in the know (and that's NOT me...)
The best way to approach this is in-car and to then decide what components you want, decide where you want them, look at the various pre-drilled and tapped mounting-holes in the block and heads and go to work. There are just SO many possible combinations of just alternator, alternator AND P/S, alternator and P/S AND A/C, then A/C - no P/S and then all of the different types of alternator units and P/S pumps and A/C units, that I have never invested in having nice CNC stuff produced for any of it! I am thinking about it now for my car though - based on what worked for me (no A/C and only P/S for the street car and no P/S OR A/C for the race car). I am also using a much smaller, but powerful alternator than the standard Milano unit that others likely won't use, so it remains a custom application - no matter how you slice it!
When Jonnie was still at G2, they did some custom welded-steel brackets for Jes on his 24v street car (before it was decommissioned). It wasn't perfect though (the rear of the P/S bracket needed shimming for example). Big Jon over at Hanson made a rough copy of that bracket for me now (but it still needs spacing to align it properly) and I made my own bracket for the alternator using a combination of the standard cast-iron sump bracket from the Milano and a "universal" alternator kit. I also made my own for the alternator on the race car from welded steel (with some help from one of the fab. guys at G2 - when I was building that car)!
Elaborate enough for ya!?
