Car Updating And Development

As the title states I'm at a bit of a cross road with our current car(s). We bought and built from the frame up two Carbir DS3 chassis 1 and 2. Over the seasons we have added small updates here and there, overhauled the cars a few times and always had the cars in tip top shape and no expense was ever spared. We took part in mostly club racing and liked the idea of taking it further but we liked keeping this as family oriented as possible as it was always time well spent. Fast forward to now, the cars have not been updated to be as competitive on the national level and would maybe struggle a little. I am tossing around the idea of taking one of the cars and going the Zetec conversion route. Reason being its more modern and a bit more durable and from what I read last longer between rebuilds when compared to the pinto. I understand the conversion is a major investment and I need more information before I pull the trigger on this. I am looking for information from drivers, mechanics, or crew about the pros and cons about this. I apologize if this has been talked about a handful of times but with a decision this expensive its good to hear what you guys have to say. Below is a picture of the current engine configuration and car.