What do i do now? V6 dilemma

[VhantaBlack98]

Been wrenching away on my 98 single port v6, replaced the head gaskets, reassembled everything and got her running pretty good again. Even managed to run her around a little to make sure my head gasket repair worked. But for the life of me, I couldn't get the coolant to get past the thermostat and back into the radiator, and couldn't get the radiator fan to kick on. Figured out I needed to bleed the cooling system of air. So I added some coolant to the bleeder valve by the thermostat and noticed coolant leaking out the back of the passenger bank cylinder head. Idiot before me used a rubber freeze plug. So now I'm at a loss of what I'm supposed to do.
If i replace the plug with another rubber, it won't last long. If I replace it with a metal plug, I'll have to tear down and replace all those gaskets again. If I replace the cylinder heads, it'll set me back a lot of money. If I switch to split port top end, it'll also set me back a lot. Im just at a loss and in need of an UNBIASED opinion on what I should do.
I've already decided I'm gonna keep her V6 for a good while at least. I'm not ready to swap in a V8, so please don't criticize me for this choice.

 

[wmfateam]

Is this a daily or more of a project/weekend car?

 

[VhantaBlack98]

Is this a daily or more of a project/weekend car?

I plan for her to be a daily. Something fun to drive a few miles at most a day, maybe more depending on where meets are.

 

[96blak54]

Sometimes ......while ownership of a mustang.......you just have to pull the engine. And if you can pull the engine, itll make installing a freeze plug a little easier and you wont have to unbolt the heads

Just simply correct the issues you have and dont try to "upgrade" with different parts. Pulling an engine is far more easier than trying to work on an engine in the car.