Goals for Florida 70.3 and Sauna training

I ran the Disney 70.3 in 2005, and PR'd with a 4:35
Swim 34
Bike 2:28
Run 1:24
Remainder of time in transitions.

So, am I stronger than I was 2 years ago?
My swim is a bit weak lately, but 34 (no wet suit allowed) should be like a moderate swim for me. I am hoping for 33 or so.
The bike? There is no doubt I am stronger than I was in 2005. I remember there were favorable winds that year. Assuming we have a neutral day...I should be able to improve from my prior 22.7 mph ave to 23 or so, and gain a couple of minutes. So, I am hoping for a 2:25-26.
The run? I just dont think I am capable of running a 2:24, esp off a 2:25 bike.
I do think that a 1:28 (6:45 pace) is achievable off a bike split of 23 mph.

So where does that leave me? 4:26 without transition. Looking at 2005, most of the combined pro's transitions were around 5-6 minutes. Top age groupers 6-8 minutes. You have to run over 200 meters from the water to the bike, which is about a minute easily. So, if I reach my time goals, a PR of 4:32-33 should be within my capability.
The problem? I want to break 4:30. This is the dilemma. This means I may have to push the bike very hard, try for maybe a 2:22, then try to run 1:28. I dont know...I will have to dig deep on this one. Unfortunately, the transitions may prevent me from nailing a "great race".

We are thinking of the 70.3 worlds in November if we get a spot at this race. Now, give me a wet suit, now I am under 30. Take off an average 2 minutes of transition time...Yeah, now I am hovering around 4:26. It may be worth the trip down there.

Sauna training:
I forgot to mention that I started sauna training last monday. Training means just sitting in the sauna, not actually exercising in it...that would lead to rapid demise.
I am trying to adapt a bit to the heat in Florida (its been in low-mid 90's) by using the sauna. I have done this for CDA past 2 years as well as Kona, and it helps.
So, I did 150 degrees for 10 minutes on Mon, wed, fri, sunday last week.

This week: 170 degrees for 12 minutes: Monday and tuesday
170 degrees for 15 minutes wed and thursday.
I pour water on the heater so it makes the sauna very humid, not just the dry heat.