I think everyone should build their car the way they want. This is for a friends car, not mine. I don't have any interest in a bowtie anything… But, since he is interested in going that route, I'd rather have him with a Plymouth on the road with a bowtie engine than a plymouth at the crusher, or stuck in a garage.
I know the parts can be fabricated, but a kit takes out some of the guess work, because it's already done for you. If he had a kit delivered to his house, I'd be more likely to have the car on the road sooner than later.
I know these old mopar cars don't get a lot of love and aftermarket support. Just throwing it out there to help him out