Moving Windows 7 Home and Hard Drive to Older Computer

Hello to all. It's been months (yrs) since I have been on here. Here's my situation.

I have my older HP Pavilion 775e desk top running XP Home. (Was the wife's PC)... I also have (mine) a HP Pavilion p6750p desk top running Windows 7 Home. I would like (think I can) transfer the Windows 7 to the older HP 775e computer. Here's how I hope to perform.
I have a (New) A7N8X-LA 5187-4113 motherboard...Exact same motherboard as the old XP motherboard, and remove the Hard Drive from the HP p6750p computer and install it in the HP 775e PC along with the new motherboard. Since I have the new Motherboard and Hard Drive from the Windows 7 computer. Will I be able to install Windows 7 on the new A7N8X-LA motherboard and hard drive in the old XP machine?

RolandJS said:

If you're satisfied that your backups of your data files are restorable -- I say go for it, carefully, no hurry. Windows 7 will balk on whatever drivers are not found in the old computer, but, you should be able fix by downloading manufacturers' drivers.

When it comes to playing with computers, I'm not in the top 10 in the transferring or making things work.

The reason I would like to do the this is to take the HP p6750p computer and install a new (clean) hard drive so I can install Windows 10 when it is available (free download) this July.
It would appear to be a easier situation than... installing a new full version of Windows 7 home on the HP 775e XP machine, and install Windows 10 over the Windows 7 HP p6750p PC.