Ok efi guys i have some questions for you.1)Did you get a new tank with the pump in the tank or just use the old one(if you used the old one how did you convert it and what did you use)?2) why did you go that way? 3)do you have any problem with your set up? 4)what did you use for the lines and where did you get them? 5) and what was the total for the way you went.

I kept the old tanks. I didn't want to drop $500 on a tank at the time. I also don't like how the larger tanks hang lower.

I used a low pressure (carb) fuel pump at the main tank, then an accumulator, then a high pressure pump . I plan on using another low pressure pump to feed the aux tank into the main, so I can regain the capacity.

Something like this:
http://www.bcbroncos.com/EFI%20plumbing ... 20mark.pdf

I also found a better accumlator than the BCB set up:
viewtopic.php?f=5&t=3874

I used 3/8" & 5/16" steel & rubber fuel line. There is special high pressure rubber line for EFI, you'll want to use it between the high pressure pump and the motor. Anywhere else is low pressure & can use traditional rubber fuel line for a carb. Its hard to say what it cost, probably $200+ for the pumps and acumulator. The EFI rubber hose was expensive, like $7/ft.

We kept the old tanks too. We ran an electronic fuel selector from a ford has inlets and returns for both tanks, then a low pressure pump to an accumulator the the high pressure. It has worked great. The only problem we have had is the low pressure failed this year.

I don't have hands-on feedback, but am planning to upgrade to an EFI tank before I switch over from a carb. I ripped out my aux tank last year and haven't missed the range (I already have a 23 gallon tank). I called Northwest Metal Products, the people who make bunches of the EFI tanks out there a few months back and they had said the additional baffling in the EFI tanks can make a big difference. I also want to get away from a strap mounted tank to one that mounts with a bracket as I dislike straps.

I've got the BC tank. At the time, I elected not to go with the in tank pump but wish I had since. I've burned up 2 EFI pumps because my pump is too far away from the tank. The bigger tank is so much nicer than having the dual small tanks. I did that on my EFI for a couple of years and could never get the return correct. It would always return to the opposite tank than what I was running on. Tried a couple of different 6-port switches and none seemed to work the way they are supposed to, so I went with the big tank and haven't looked back.

You could consider another alternative. Ford used a frame mounted fuel pump on some of their 80's and 90's trucks and vans that had dual tanks. It is mounted on the frame just below where the driver sits. Plenty of them available at the U Pull and Pay's.

I used that pump as my high pressure pump, in conjunction with a low pressure pump & accumulator. Working great for 1 year now.

That is the pump that I have burned up 2x. It's completely my fault because I didn't, and haven't yet, put a pusher pump & accumulator on. But it's a good pump.