Depending on your bent, this topic will offend or thrill you. I just acquired a 1948 P15 sedan basket case that is overall in decent shape but realistically not restorable unless you are a true purist.
Short history:
Bought for the frame condition by the PO to make a restomod type driver with a busted tranny and some rust issues
Sold it to his brother in law who got another transmission and rebuilt the motor
Sat in a garage for 30 years
Now our plan (purist, please leave or risk being offended):
We have been racing 24 hours of LeMons for about 4 years and intentional moved to progressively less suitable vehicles for endurance road racing.
What our team does...https://www.facebook.com/BadDecisionsRacing
What LeMons is...http://www.24hoursoflemons.com/ ...and it is NOT DEMO DERBY.
What we have learned over the years is power is not the key to success. To drive this point home, our van is 6th slowest of 76 cars (fastest lap) and finished 35th with 2 hours of down time for repairs. In order of importance:
Team coordination and dynamics
Reliability
Brakes
Handling
Racing Stint length
Straight line speed
So we plan to run the flathead the first 1-2 races at least. I actually believe the flat head can easily be good enough but we may need a taller rear end (we learned that the Buick 3800 in our van, coupled with its new manual transmission works best just leaving it in fourth...and it hits 85 mph on the straights pulling many cars in the process). So after repairing minimal floor pan rust and putting the car back together we want to do the following:
Front Shock relocation
Disc brake conversion (we put Corvette C5 calipers on the van after melting stock caliper, twice) front
The Moog CC850 springs up front
Appropriate two piston master cylinder (suggestions welcome)
New brake hard lines...from experience in the Midwest just easier
Boil and rod the Radiator
"Clean" the fuel tank with nuts, paint thinner and lots of shaking
New rear shocks (do they need relocation for modern shocks?)
Potentially new rear axle with disc brakes and a higher ratio
I currently have no issues with the 6 volt system and for racing, points are OK on the ignition.
What I do not know:
Best tire size for our 15" rims for max thread width without rolling or rubbing
Better alternate carbs...or run the old one
Method for keeping wheel bearings happy (long story, but very common failure at races)
"Best" rear end ration to cover 45 mph to 80 mph speed range (I know the limitations of the stock motor so the upper end is inspirational)
We take the LeMons experience seriously but the racing is just a side benefit. We are quick for our class but not nut jobs about winning. The community is amazing and spending time with like-minded folk is a blast.
So I would appreciate a LOT of help for phase 1 and when (not if) we go to re-power I will need lots more. No comment is too insulting or inane so hit me with it!