well the hole is there. it has just been filled. the way i done mine was to drill it out and replace the last alan key head bolt with a standard nut and bolt setup. just make sure you get nylox nuts or you will be forever tightening them.
statesman seats though will fit straight in.
personally i would probably just go statesman seats over caprice one's but its up to you.
The seats im eyeing off would look great in my car,same colour as inside and in good nic, bit pricey tho so i may indeed take your advice and get stato seat,just waiting to see how may finances go till mid next month before i decide,but i'd look up everything first.thanx again mate