Long hard start

Cousin's truck is having a 20 second start time. I will try to list the symptoms and maybe someone will know the probable answer. First I'll start with a history of the truck, it's a 2000 V6 2WD, that has always had starting issues. I have personally replaced 4 or 5 starters on this truck in the past 5 years, and I'm thinking the next starter is going to be number nine, since he's owned it. I do not know why this truck is eating starters. Most of them have been autozone rebuilds, but even a rebuilt starter should last more than a year. Let's begin,
Fresh plugs(less than six months)
Clean MAF
Fresh fuel filter
Fresh air filter
Fuel pressure has not been tested(needs a special setup on this engine)
Voltage seems fine, relatively new battery
I installed a push button start on the starter as the circuitry from the key failed
Circuitry had been previously been totally screwed with by previous owner
No abnormal starter/alternator noises
Someone mentioned a Fuel Pressure Regulator, which has been purchased, but not installed.
There is not much of a difference between a hot start and a cold start in this situation, the owner says it's a little better doing a hot start, but not a lot(18sec vs 20sec). When it starts he claims he has full power even above 60mph, which makes me question if it's having fuel starvation issues. Someone else claimed it could be burning up starters because the battery-to-starter wire may be intermittent, causing early degradation of starters.

At this point the starter is going to be replaced by an OEM Toyota starter, if these symptoms turn on any lightbulbs in anyones' head, please do reply. The rate of starter failure in this truck is between 6-10 months. I'm also not throwing out fuel issues either.

One more bonus question, is there a trick to replacing the fuel pressure regulator on these 3.4L's? I looked at it and it seemed very tight, looks like the wiring loom covering it needs to be unbolted and moved out of the way, but even then it seems pretty crappy. doable but crappy.

Thanks

 

One more thing I am wonder about is starter spacing. I have replaced starters that needed starter spacers, to make sure the starter is free of the flywheel when it retreats, could this be the case on this engine? No starter spacers have been provided, or mentioned in the literature. I am thinking this is a possibility, but I am not sure, I have not worked on a lot of toyota engines. It may be the thing of the past, it certainly was a thing with my late 80s benz.

 

Does the engine crank fast when trying to start or is the starter slow and lugging?

 

It sounds like a healthy turnover, it just doesn't want to start, but again it's not my truck, I don't start it every day. In my opinion it starts like it always does when it starts as it's supposed to. But it just keeps turning until something "happens" and it roars to life. Which may be indicative of fuel system issues, which is why the fuel pressure regulator, or pump may be in question. But I know this truck has always had a problem with starters, I'm on the fence.