If you get the same brand electric jacks as what's on there now, they will bolt right in place of the existing jacks. No changes necessary. If they're not the same you may need to drill some holes. Big deal.
You'll have to figure out how to run wires.
But, this is a 14 year old camper... Is it really worth $1500 to add electric jacks to a $3000 camper? It won't be worth $4500 when you're done. It will be worth $3100.
Every time I load or offload, I wish I had electric jacks. Then I go shopping. Then I realize that I'm thinking about putting a $1500 set of jacks on a $1500 camper. Doesn't make sense.