Do you have a return or returnless system? The returnless trucks have a larger bucket that makes it much easier than the return buckets. I modified my return bucket for twin 255 which required removing a lot of the bucket. For wiring I used two hotwire kits which I modified to use a Hobbs switch to activate the second pump. I also used a stainless steel 1/2" barbed tube fitting from McMaster-Carr with 3/8" submersible hose. It was a bitch getting the hose on the y-fitting but the ID of the 3/8" was quite a bit smaller than the id of 3/8" hose and I didn't want that bottle neck right at the head of the pumps. I wired the positive lead to each pump to the factory bulkhead connector and used a ss bolt thru the hat for the grounds to both pumps.