Sometimes people overhype iPD and others selling non-Volvo aftermarket parts as supposedly cheaper supposedly direct fit replacements for Volvo parts. I ran into a problem installing a "direct replacement" radiator on my 240 - it simply did not fit the same as the stock radiator despite claims to the contrary on the box and from FCP Groton. So...when it was time to replace the radiator in my 740 Turbo, I got a genuine Volvo/Blackstone radiator (superior quality versus Nissens, IMO, not a speck of rust and improved metal connections for the hoses) for LESS money than Nissens buying it from Borton Volvo over the internet. It installed -perfectly- including the temp sensor for the fan (very tight fit) - except I had to use tie straps in place of the screws holding the fan shroud on (the hole size was changed I think). If your second try doesn't work out, return your Nissens radiator (if they let you) and get a Volvo part from Borton. Good luck...

Zack (musician when I'm not an engineer)
1980 245DL M46 278k
1988 745T+ M46 209k