I could be wrong but I believe 74 still used manifold as opposed to the later years used ported. That said it comes down to understanding the difference and your particular engine setup. Manifold vacuum is greatest at idle and goes away as "you stick your foot in it", this good for economy if...
Personally , I am quite fond of Slick 59 spray lube. I am a retired car hauler and used it for years on the chain ratchets on truck and trailer. If no where else, it can be found at Ace Hardware.
There is a company called Wheelskins that sells an excellent DIY real leather steering wheel wrap. They have gotten IMO pretty pricey in recent years but are great quality. Figure on at least an hour to install.
One thing I noticed not mentioned. Have you corrected the speedo for the 36' tires? If not , you are putting more miles on than indicated, hence lower MPG.
IMPO regardless of other considerations, if the lettering is Goodyear,BFG or Firestone(although Firestone are never to be used) out is acceptable but all others cheapen the look.
That's what I meant earlier about the ratio being the hard part. I know there were at least a dozen here locally in 77 & 78 as I was customizing new trucks for resale then and that's how I ordered them. One of those surfacing would be ideal. I have found a couple over the years but all managed...
The existing front axle is whatever GM used at the time. The burb has been in storage for the last several years, but the issue has always been there. Just in case you missed earlier I have had this for 43 years. Unless I am wrong 1 more time GMT800s are the body style after square bodies and...
Brakes are my main goal. GM in their infinite wisdom when they started factory 4x4s took the skinny rear drum system and put it on the front along w/adding about 800 lb. Terrible math for braking. I have had this suburban 43 years and have run Velvetouch full metallic lining in order to makeup...