Further update...I suspect I have a multitude of issues, but my most pressing that I'd like to sort now is the venting. My '74 still has the stock setup from the expansion tank to the engine bay (charcoal canister removed), but I think that the line isn't flowing that well and may actually be broken somewhere in the cabin. The easy solution I've found is to run some sort of 'euro vent' via the trunk and bypass the tank for now. I plan to find a universal charcoal canister (I'm open to suggestions as to which one) and run through the expansion tank once I've proved that venting directly via the euro way solves some of my issues. Also, after some research I've decided to move the idle jets up to 60. I'm still on 145 mains and the car seems to be running pretty rich based on it's "bucking" at times, which is oddly worse with more gas than less. Some of the posts I've read about the jetting being somewhere in the 135 range when running idle jets as large as 60. So, plan is to do euro vent tonight and see how that is and then move main jets to 135. With that said, my last 215 miles on the car with 145 main jets got me a good 24mpg (per odometer), which is better than I've ever gotten with the 32/36 prior. So, seems to be going on the right track...