i was planning to buy a lip for my 88 crx but the problem is that its for 91 crx.. i was doing some research on it and said it could fit but have to shaved something off.. is this true?

also my crx has been eating a lot of gas.. i pumped a full tank and only got 130miles.. its sucks diCk.. does anybody know why this is happening.?

the mods i have is

STR fuel rail.. all my other fuel upgrade is stock...