Steering wheel retaining nut

Stop replying everybody
I worked it out myself using process of elimination:
M16 x 2.00P Nyloc Nut
I'm replying to my own post as someone may search for this in the future.

There's a really good thread thread on turbosport.

http://www.turbosport.co.uk/showthread.php?109172-Thread-thread&highlight=escort+bolt+thread

Here's a copy.

ENGINE
Crossflow
Engine bolts (in block): 5/16 UNC.
1300-1600 flywheel bolts: 3/8 UNF.
Oil pressure take-off: 1/8 NPT for 681 blocks & 1/4 NPT for 691 and 711m.
Thermostat Housing: 5/16 UNC 25mm long
Inlet Manifold: 5/16 UNC 25mm long
Exhaust Manifold: 5/16" 25mm long (UNF for the nuts and UNC in the head)
Oil Pump: 5/16 UNC 25mm long
Rear Crank Cover: 5/16 UNC 25mm long.
Water pump x2: 1/4 UNC
Water Pump x1 (alternator bracket one): 5/16 UNC 25mm long
Sump bolts:
Oil Breather Box:
Distributor to block: all 1/2" long
Front Timing Cover: all are 20mm apart from 1 which is 43mm long
Crossflow water pump pulley / fan retaining bolts - 5/16 UNC for MK1s, Mk2 and most remanufactured pumps are M8


Pinto
Pinto spark plug thread: M18x1.5.
Pinto oil pressure switch: 1/4 NPT (pipe thread).
Pinto alloy sump to engine bolts: M6x18
Pinto alloy sump plug: M12x20.
Pinto block drain: 3/8 NPT

Gearbox & Bell housing
RS alloy bellhousing to engine bolts: M10x1.5 (30mm long).
Bellhousing to type 9 gearbox: M12 x 1.5 FINE

AXLE & PROP
Propshaft to Atlas/English axle bolts: M10x1.0mm pitch.
Drum brakes to english axle Mk1: 7/16 UNF.
Drum brakes to english axle Mk2: M12x1.5.
Mk1 Axle U bolts: 7/16 UNF (20tpi)

SUSPENSION, STEERING & BRAKES ETC
Caliper to strut bolt (2.8i strut): 7/16 UNF.
Disc to hub bolts 2.8/RS hubs: 3/8 UNC.

Drum brakes to english axle Mk1: 7/16 UNF.
Drum brakes to english axle Mk2: M12x1.5.

Brake pipe unions metric: M10X1
Brake pipe unions imperial: 3/8 UNF

Bilstein competition/Escort RS type front insert bottom thread: M10x1.0mm.
top thread 5/8 UNF
Capri 2.8 Bilstein top nut M12 x 1.25
MK1 RS roller top strut mounts - 5/16 UNF (24tpi)
Mk1 Axle U bolts: 7/16 UNF (20tpi)
Rear leaf spring (front): 7/16 UNC

MK1 Escort Steering column top nut : 9/16 UNF

Mk2 Steering rack track rod end lock nuts: M14
MK1 rack-to-crossmember bolts: 5/16 UNC (18tpi)
MK1 Escort anti-roll bar bracket retaining bolts - 5/16 UNC

Mk1 Escort wheel studs: 7/16 UNF.
Mk2 Escort wheel studs: M12x1.5.
Group 4 wheel studs: 1/2 UNF.
Capri wheel nuts: M12x1.5mm

BODY/MISC
Escort seatbelt mounts: 7/16 UNF
Cross member to body: 3/8 UNF
Mk2 Escort - most bolts are M8 (ie bonnet, boot, hinges, etc)
Large inner tank outlet 3/4 BSP on Mk1 and most probably Mk2
MK1 Escort window winder / door release handle screws - 3/16 (no.10) UNF (32 TPI)
MK1 Escort interior door handle screws - 7/32 x 24 tpi