i have stock valve covers i am going to polish but not sure if they will be tall enough for my valve train _ 1.72 RR's, heavy springs, comp cam xe-270-hr-12 or part number 35-312-8 cam for 1.7 RR's, INT .544 and EXH .566. (also hope this will work with stock pistons.) could the xe-270hr-14 work with the 1.7RR's? its the same cam as above but supposed to be used with 1.6RR's. also whats the proper way to measure for pushrod length. i think the stock might be ok but not sure. i dont want to use them with the heavy springs and aggressive cam anyway. thanks for reading, hope someone can make sense of my incoherent rambling.