With the bell housing back on with no pressure plate installed, I use a magnetic based dial indicator to zero in the bell housing. The magnetic base is stuck on between the [ clean ] flywheel bolts , the indicator is setup to run on the large surface hole of the bell housing that the transmission bearing retainer fits in. I mark the harmonic balancer every 45 degrees . Turn the crankshaft from the front crank bolt. Take a reading , write it down at each 45 degrees till you complete a full rotation. This will tell you whether your bell housing is good to go or not. I think .010 total indicator run out is acceptable. Google that for proper info. If it is out contact Robbmc for the proper Mopar offset dowels.