Slant six or v8 swap for use in a truck

I'm biased towards the slant 6, so keep that in mind with my answer.

You've already admitted in your own words the slant 6 does everything you want to do with your truck now. You simply would like maybe a little more leverage (gear).

You said "the slant will never sound or perform like a V8" and that's true. It's also true a V8 will never sound or perform like a slant. The 225 has a mechanical advantage over any factory Chrysler V8 in its 4.125" stroke. That's maximum torque just cracked off idle. Great for a truck. Chrysler knew this and didn't shy away from putting the slant 6 in trucks as big as a Dodge D500 dump truck. They made millions of them. While it's true they never won any races, they did the job and did it well.

The slant 6 is different. When we drive Vixen (my 64 Valiant) to any and I mean any car event, everyone always expects to see a small block and the look on their faces when they see the slant 6 is priceless. She usually gets tons of attention wherever we go. Look around if you go to cruise ins and see how many small blocks there are. It gets boring.

You already admit you know the slant will never be a V8 and you're right. Conversely, the V8 will never be a slant, either. It's a decision you and you alone are going to have to make. Whichever way you go, keep us posted!