Across the counter push rods from Summit range from 7.342 - 7.550 but it's all about valve train geometry. I hate to see you throw your beautiful car back together so quickly.
First, you have aftermarket rockers. They are different than stock so it is necessary to find the correct length pushrod for your combination. Most rocker arm manufacturers want about or no more than 2 threads showing on the bottom of the adjuster. If there are to many threads, the adjuster will be subject to too much pressure. If there are to little threads, the cup will be to high to receive oil from the oiling hole in the rocker arm. Just a guess but I think your original pushrods were too long.