[jorgensensc]

Huck,
The sidemarker install was a little bit of a pain in the a$$, but it wasn't really that hard, just takes a little thinking. I will post it as soon as I get all my info rechecked. I hope to be able to give you specific details on the install, like dimensions, bolt sizes, etc. I did this on a stepside, so you might have to check a few things with other fleetside members.

orange72350,
THe tank is a 21 gallon tank

yellow72custom,
Hopefully put some speakers back there!!!

jamie72,
I vented the tank to the fuel filler neck, it had a vent tube for it attached. I also vented the other line to the carbon cannister. Hope this answers your question. I have heard of people using a vent breather (you can get from parts store)

nu2-72,
These are plain blazer tanks. They call it a conversion because it comes with the straps, sending unit, tank and necessary bolts to mount all in 1 kit for a low price.
As for the neck filler size, they are using the factory size. I know that it is not a convenient size, but if they change it to 1 1/2" neck, then what about the 2" filler necks? Both are common. I will agree that the hole size on the mounting flange could be bigger, but it only took me about 2 min. to wallow those out a little. They were only a little bit too small. Again that is a detail and I do agree with you.
As for lining up the neck with the sidemarker, it is not that far off. I don't think it would be fair to ask them to modify the tank for just sidemarker conversions. What about those that do bed floor fills?
If they did these changes, they will probably have to charge more for the retooling.
Please remember, putting the tank itself in only took about 2 hours. I spent the rest of the time working on the filler neck conversion. You can easily get this done in a day if you had a complete parts list before you start. That's what I hope to provide to the members here. It really wasn't that hard, I promise.

Any more questions??

Hope all this helps y'all!!