[randy500]

I started reading your build a couple weeks ago, I like it.

Looks like your working out the ac compressor mount. I bought the Cummins high mount freighliner parts and modified the alternator bracket so I could use the dodge denso unit. When I was doing the changeover I felt like I could have modified the low mount ac bracket like you are working on.
Looks like you will have to change water necks for belt clearance.
When I put the ac on mine I tried the tensioner up high like you have yours sitting (4bt style) I hade very little belt clearance and the belt length had to be spot on, took a bunch of fitting and belt searches and in the end the tensioner did not tension the ac compressor enough which caused it to chip from belt skipping and when that happens The tensioner has wild adjustment fluctuations. It was jumping crazy back and forth trying to keep tension.

I read it’s best to have the tensioner last in-line and that’s what I did, I put it down by the frame rail, fixed the problem.

For belt length I cut my old dodge belt then used it to wrap and mark needed belt length, laid it out flat and measured the length then found that length online in the gates or dayco online catalog. Belts are $50 or so local but I found the ones I needed on rockauto, amazon and eBay for about $20 or less.
There are plenty of 8rib belts in the length you need...that had me worried too.

For your tach, you can get a tach signal from the 2nd gen crank sensor, I wrote up how to do it, just set your aftermarket gas tach to 4 cyl mode and it will read correctly (2 pulse per revolution) which you get from the 2nd gen sensor.

You have probably already looked it up but a 1st gen fan hub will move the fan up and center I believe, it also gives you .75” or so of more fan to radiator clearance, the pulley is different from 2ng gen so you need it with the fan hub.