Flex plate to convertor gap

Did you use the bushing in the crankshaft register to reduce it's diameter? A 71 318 has the large diameter crankshaft register. The 64 torque converter has the small diameter register. If you didn't use the bushing your going to beat the **** out of the torque converter bushing and most likely bust the flex plate. Regarding the gap between them, just pull the converter forward and bolt them together.